1. Field of the Invention
The present invention relates to an antenna for a non-contact type IC card. More particularly, the present invention relates to an antenna for a non-contact type IC card using a plane coil in which a conductor, which is formed by punching or etching a metal sheet, is wound, in substantially the same plane, a plurality of times. Also, the present invention relates to an antenna frame for a non-contact type IC card. Also, the present invention relates to a non-contact type IC card.
2. Description of the Related Art
As shown in FIG. 10, an IC card includes: a rectangular-shaped plane coil 100 in which a conductor wire 102 is wound a plurality of times; and a semiconductor element 104. The above plane coil 100 and the semiconductor element 104 are interposed between two sheets of resin films 106 made of polyvinyl chloride (PVC) on which letters and other items are printed. The two sheets of resin films 106 are made to adhere by an adhesive layer made of polyurethane resin. This adhesive layer seals the plane coil 100 and the semiconductor element 104.
When the thus formed IC card passes in a magnetic field formed by a card processor, electric power is generated, by electromagnetic induction, in the plane coil 100 of the IC card. Therefore, the semiconductor element 104 is started by the generated electric power, so that communications can be sent and received between the semiconductor element 104 of the IC card and the card processor via the plane coil 100 which functions as an antenna.
The plane coil 100 used for the above IC card is conventionally formed in such a manner that a covered electric wire is wound a plurality of times.
However, when the covered electric wire is wound so as to form the plane coil 100, it is difficult to reduce the manufacturing cost of the plane coil 100 and also it is difficult to mass-produce the plane coil 100.
Therefore, in order to form a plane coil by means of punching or etching by which the plane coil can be mass-produced at low cost as compared with a plane coil formed by winding a covered wire, the present inventors proposed to use a lead frame for an IC card, which is shown in FIG. 11, in the manufacturing process of the IC card in the specification of Japanese Patent Application 11-279242.
The lead frame 200 for an IC card shown in FIG. 11 is made by etching or punching a thin metal sheet. Each plane coil 202, 202 is partially connected with the inside frame 204 and the outside frame 206 which are respectively formed inside and outside leaving a predetermined interval between the plane coil and the inside and outside frames. That is, the support sections 208, 208 extending from a plurality of positions of the inside edge of the outside frame 206 are respectively connected with the outermost conductor 203a of the plane coil 202, and the support sections 210, 210 . . . extending from a plurality of positions of the outside edge of the inside frame 204 are respectively connected with the innermost conductor 203b of the plane coil 202.
The plane coil 202 is substantially rectangular. In order to enhance the rigidity of the plane coil 202, there are provided bent sections 22, 22 . . . in each straight line sections of the plane coil 100. Further, in order to integrate the conductors 203 on the circumference of the plane coil 200 into one body so as to prevent the conductors 203 from breaking up, the conductors 203 on the circumference, which are adjacent to each other, are connected with each other by the connecting pieces 26, which are arranged at a plurality of positions.
In the case of the lead frame 200 for an IC card shown in FIG. 11, when the plane coil 202 is separated from the inside frame 204 and the outside frame 206, the support sections 208, 208 . . . , 210, 210 . . . cut off and also the connecting pieces 26, 26 . . . are cut off. After they have been cut off from the plane coil 202, the conductors 203 on the circumference of the plane coil 202 tend to break up. Therefore, in order to prevent the conductors on the circumference 203 from breaking up, a plurality of tape members 214, 214 . . . made to adhere onto the plane coil 202. In this connection, the plane coil 202 onto which the plurality of tape members 214, 214 . . . are made to adhere is electrically connected with the electrode terminal of the semiconductor element 216 and the terminal of the plane coil 202.
According to the lead frame 200 for an IC card shown in FIG. 11, when the plane coil 202 is separated from the inside frame 204 and the outside frame 206, even if the support sections 208, 208 . . . , 210, 210 . . . are cut off and also the connecting pieces 26, 26 . . . are cut off, the conductors 203 of the plane coil 202 are fixed by the tape members 214. Therefore, the conductors 203 on the circumference can be prevented from breaking up. Accordingly, the plane coil 202 can be easily handled.
However, the plane coil 202, which has been separated from the inside frame 204 and the outside frame 206 so that the plane coil 202 is simplified (this plane coil will be referred to as a xe2x80x9csimplified plane coilxe2x80x9d), must be interposed between two sheets of resin films, on the outer surface side of which characters are printed, so that it can be formed into an IC card. Therefore, it is necessary for the simplified plane coil 202 to be air-absorbed and/or positioned.
When consideration is given to the manufacturing cost of the IC card, it is necessary to automatize the air-absorbing and positioning work of the simplified plane coil 202. However, on the plane coil 202 shown in FIG. 11, there are provided no portions useable for air-absorbing and positioning the plane coil 202. Therefore, it is difficult to automatize the air-absorbing and positioning work of the simplified plane coil 202.
It is an object of the present invention to provide an antenna for a non-contact type IC card, an antenna frame for a non-contact type IC card, and a non-contact type IC card characterized in that the air-absorbing and positioning work for a simplified plane coil can be easily automatized.
As a result of an investigation made by the present inventors to solve the above problems, they have found that the sucking and positioning work of the simplified plane coil can be easily automated when a plurality of projecting sections are formed on the outermost or innermost conductors of the plane coil, and these projecting sections are used as suction pads or alignment marks in the case of sucking or positioning the simplified plane coil.
According to the present invention, there is provided an antenna for a non-contact type IC card, the antenna comprising: a plane coil formed by punching or etching a thin metal plate in such a manner that a conductor line is wound several times on substantially the same surface; and at least one projection integrally formed with the conductor and extending therefrom inwardly or outwardly so as not to contact an adjacent loop of the conductor line, the projection being located at any desired position to be used as a suction pad, an alignment mark or a positioning guide when the plane coil is sucked or positioned.
According to another aspect of the present invention, there is provided an antenna for a non-contact type IC card, the antenna comprising: a plane coil formed by punching or etching a thin metal plate in such a manner that a conductor line is wound several times on substantially the same surface, the plane coil having respective terminals at innermost and outermost ends, the innermost terminal is provided with accommodation hole; a semiconductor element having electrode terminals and arranged in the accommodation hole; a circuit film comprising an insulating resin film and a circuit pattern formed on the insulating resin film, the circuit pattern electrically connecting the electrode terminals of the semiconductor element to the terminals of the plane coil; and at least one projection integrally formed with the conductor and extending therefrom inwardly or outwardly, so as not to contact an adjacent loop of the conductor line, the projection being located at any desired position to be used as a suction pad, an alignment mark or a positioning guide when the plane coil is sucked or positioned.
According to a still another aspect of the present invention, there is provided an antenna frame for a non-contact type IC card, said antenna comprising: a plurality of plane coils formed by punching or etching a thin metal plate in such a manner that the plurality of plane coils are longitudinally and continuously arranged at a predetermined interval, each plane coil comprising a conductor line wound several times on a substantially same surface; a frame member partially and integrally connected to the plurality of plane coils so as to hold the latter; each of the plane coils comprising at least one projection integrally formed with the conductor and extending therefrom inwardly or outwardly, so as not to contact an adjacent loop of the conductor line, the projection being located at any desired position to be used as a suction pad, an alignment mark or a positioning guide when the plane coil is sucked or positioned.
According to a further aspect of the present invention, there is provided a non-contact type IC card comprising: a plane coil formed by punching or etching a thin metal plate in such a manner that a conductor line is wound several times on substantially the same surface; and at least one projection integrally formed with the conductor and extending therefrom inwardly or outwardly so as not to contact an adjacent loop of the conductor line, the projection being located at any desired position to be used as a suction pad, an alignment mark or a positioning guide when the plane coil is sucked or positioned.
According to a still further aspect of the present invention, there is provided a non-contact type IC card comprising: a plane coil formed by punching or etching a thin metal plate in such a manner that a conductor line is wound several times on substantially the same surface, the plane coil having respective terminals at innermost and outermost ends, the innermost terminal being provided with accommodation hole; a semiconductor element having electrode terminals and arranged in the accommodation hole; a circuit film comprising an insulating resin film and a circuit pattern formed on the insulating resin film, the circuit pattern electrically connecting the electrode terminals of the semiconductor element to the terminals of the plane coil; at least one projection integrally formed with the conductor and extending therefrom inwardly or outwardly so as not to contact an adjacent loop of the conductor line, the projection being located at any desired position to be used as a suction pad, an alignment mark or a positioning guide when the plane coil is sucked or positioned; and a pair of external films between which the plane coil is disposed together with the semiconductor element and the circuit film.
In the present invention, when the projecting sections are formed in the conductors arranged on the outermost loop and/or innermost loop composing the plane coil, the projecting sections can be easily formed.
The conductors composing the plane coil are fixed with resin, which is filled in the spaces between the adjacent conductors of the plane coil and does not protrude out from the upper and the lower surfaces of the plane coil, so that the adjoining conductors can be held at predetermined intervals. In this way, the conductors of the simplified plane coil can be prevented from breaking up and the handling property of the simplified plane coil can be enhanced. Further, resin for fixing the conductors is not protruded from the upper and the lower face of the plane coil. Therefore, even when the simplified plane coil is interposed between two sheets of resin films so as to form an IC card, it is possible to provide a thin IC card.
When the semiconductor element is arranged in a frame body which is formed by being projected onto the inside space side of the plane coil and also the electrode terminal of the semiconductor element and the terminal of the plane coil are electrically connected with the each other by wiring pattern formed on one side of the insulating resin film, the thickness of the finally obtained IC card can be reduced as compared with a case in which the electrode terminals of the semiconductor element and the terminals of the plane coil are electrically connected with each other by wires.
In this connection, in the case of positioning the plane coil by a guide pin, when a guide hole is formed in the projecting section so that at least a portion of the guide pin can be inserted into the guide hole, the simplified plane coil can be easily positioned using the guide pin.
On the plane coil used for the antenna for a non-contact type IC card, the antenna frame for a non-contact type IC card and the non-contact type IC card of the present invention, there are provided projecting sections, which project outward or inward from the plane coil, at predetermined positions of the conductors on the circumference so that the projecting sections do not come into contact with the adjacent conductors.
Therefore, in the manufacturing process of the antenna for a non-contact type IC card, the antenna frame for a non-contact type IC card and the non-contact type IC card, when the simplified plane coil is sucked and positioned, these projecting sections function as suction pads, alignment marks and positioning guides. Therefore, it becomes possible to automate the sucking and positioning operations of the simplified plane coil.